[quote=@IncredibleBee]
No I mean the original F/SN. Eight servants. Count 'em.
[/quote]

Uhhhhh... yeah, but Gil wasn't summoned by the Grail for the Fifth War. He was incarnated at the end of the Fourth when he bathed in the Grail mud and he kinda just stuck around to fuck with people's lives in the Fifth. 

Not seeing how that justifies eight Servants here, especially when the GM stated it's been decades since the last War.

EDIT: If you meant True Assassin, that's more loophole abuse by Medea and Zouken in equal parts. That normally does not happen.